Rolling mills

ABSTRACT

A rolling mill stand has two pairs of housing posts, the members of each pair defining a space therebetween for receiving one above the other the chocks for at least two rolls, a separate housing top overlying all four members and which is adjustably displaceable vertically relative to the posts, the top having a pair of parts extending sideways beyond the planes through the pairs of housing posts and means carried by the extended parts for bending the roll supported by the uppermost chock in each of said spaces. The base of the housing posts also has a pair of parts extending sideways beyond the planes through the pairs of housing posts and means carried by the pair of extended parts for bending the roll supported by the lowermost chock in each of the spaces.

I United States Patent [1113,580,035

[72] Inventors Hurry Laurence Fred Bond 3,250,105 5/1966 Stone 72/245 Halhersage; 3,364,715 1/1968 OBrien. 72/245 Dennis Stubbs; Maltby Todwick, Sheffield, 3,373,588 3/1968 Stone 72/237 9110f, England 3,394,566 7/ 1968 OBrien 72/240 [21] P 7l9l35 Primary ExaminerRichard J. Herbst [22] Filed Apr. 5, 1968 A Hen C westin 45 Patented May 25, 1971 [73] Assignee Davy and United Engineering Company,

Limited Yorkshire England ABSTRACT: A rolling mill stand has two pairs of housing posts, the members of each pair defining a space therebetween [54 ROLLING MILLS for receiving one above the other the chocks for at least two 8 Claims, 3 Drawing 118$ rolls, a separate housing top overly ng all four members and which is adjustably displaceable vertically relative to the posts, U.S. the to having a pair of parts extending Sideways beyond the [51] f Cl Bzlb 31/16 planes through the pairs of housing posts and means carried by Fleld of Search the extended for the roll upported the up- 245, 240, 241, 243, 199, 21 permost chock in each of said spaces. The base of the housing posts also has a pair of parts extendin sidewa s be end the [56] References cued planes through the pairs of housing post s and means cirried by UNITED STATES PATENTS the pair of extended parts for bending the roll supported by 3,124,982 3/1964 Nevmann 72/21 the lowermost chock in each of the spaces.

Patented May 25, 1971 3,580,035

2 Sheets-Sheet 1 INVENTORS THEIR ATTORNEY Patented May 25, 1971 2 Sheets-Sheet Z m 12 5 34 3 am F/GZ.

VI W H T L W Bm m T m s M VINC/L REM R M ROLLING MILLS This invention relates to rolling mills and is particularly concerned with the construction of a rolling mill stand, for example for rolling plate.

In accordance with the present invention a rolling mill stand comprises two pairs of housing posts, the members of each pair defining a space therebetween for receiving one above the other the chocks for at least two rolls, a separate housing top overlying all four members and which is adjustably displaceable vertically relative to the posts, said top having a pair of parts extending sideways beyond the planes through the pairs of housing posts and means carried by the extended parts for bending the roll supported by the uppermost chock in each of said spaces.

Preferably the base of the housing posts has a pair of parts extending sideways beyond the planes through the pairs of housing posts and means carried by said pair of extended parts for bending the roll supported by the lowermost chock in each of said spaces.

By carrying roll bending parts on the housing top, the overall height of the stand, and particularly the length of the housing posts, can be kept to a minimum. Previously roll bending beams have been carried in the housing windows, formed between the housing posts, the beams being interposed between the backup chocks and the base and top of the housings; asa result, the windows have been correspondingly extended and the length of the posts enlarged beyond that necessary foraccommodating the rolls.

The members of each pair of housing posts may be connected together adjacent the upper ends thereof by a rigid strap. Each pair of posts may be formed integrally with the base on which they stand and their strap as a closed frame. Alternatively, the posts, base and strip may be formed separately and secured together, as by bolts.

In a preferred embodiment of the invention, each housing post is secured to the base of the stand by a separate tie bolt extending through the post and means are provided for pretensioning at least part of the axial length of each bolt.

In order that the invention may be more readily understood, it will now be described, by way of example only, with reference to the drawings filed with the provisional specification in which:

FIG. 1 is an end view of the stand, the left-hand half being shown in section,

FIG. 2 is a side view of the stand, the left-hand part being a section on the line 11-" of FIG. 1, and

FIG. 3 is a plan view of a part of the screwdown drive.

In the form shown in the drawings, the stand comprises a massive baseplate 12 from which upwardly project two pairs of housing posts 13, 14, secured to the baseplate 12 by tie bolts 15 which will be described in greater detail later. The housing is supported on feet 16 which are secured to the posts l3, 14, the baseplate l2 and the lower ends of the posts l3, l4 lying in a pit 17.

The stand also has a separate housing top 18 which overlies the four housing posts 13, 14 and is adjustably spaced from the tops of those posts. In the housing windows 20 which are the spaces between and defined by the members of the pairs of housing posts 13, 14 the chocks of the mill rolls are slidably arranged one above the other. Chock 23 for the upper work roll 24 is nested within the upper backup roll chock 21, while the chock 25 of the lower work roll 26 is guided by inward projections 27 of the housing posts l3, 14. As shown in FIG. 2 the necks of the backup rolls 22 extend outwardly beyond their chocks 21 and carry outboard bearings 28 for roll bending. To permit the backup rolls to bow, their chocks 21 have convex bearing plates 30 (FIG. 2) engaging with bearing plates on the baseplate 12 and housing top 18, respectively.

Each bolt 15 passes through its housing post 13 or 14 and the baseplate I2 and carries at its lower end a nut 31 bearing against the underside of plate 12. Each bolt 15 has also an outwardly extending portion in the form of an integral collar 32 which is received in a shouldered recess formed in the top of the post. Extending upwardly from the collared portion 32,

the bolt has a section 33 of enlarged diameter which is slidably located in an opening in the top 18. The bolt finally terminates in a screw-threaded portion 34 which meshes with the interior of a hollow nut 35, which carries a worm wheel 36 partly surrounded by a cover 37 secured to the top 18. As shown in FIG. 3, the worm wheel 36 is driven by a worm 38 carried on a shaft 40 which is driven by an electric screwdown motor 41 through reduction gearing 42. There are two such screwdown motors 41, coupled together through-a magnetic clutch; one drives the two nuts of the pair of posts 13 and the other drives the two nuts of the posts 14. When the nuts 35 are driven by the screwdown motors, the top 18 is raised or lowered relative to the posts 13, 14, through the engagement of the top 18 with the flanks of the worm wheels 36.

In addition to the nuts 35 and screws 34, the top 18 of the stand can be adjusted relative to the posts 13, 14 by means of four hydraulic piston and cylinder assemblies 43, which are carried on lateral extensions 44 formed on the housing posts l2, 13 at their upper extremities. The pistons engage with similar lateral extensions 45 on the top 18 and itwill be appreciated that, when liquid under pressure is supplied to the assemblies 43, the top 18 is displaced vertically relatively to the posts, through the stressing of the bolt portions 33, 34.

The mill stand is provided with backup roll bending. For this purpose, the top 18 is formed with integral beam parts 46 extending outwardly above the extended roll necks of the top backup roll 22. Each beam part 46 carries a piston and cylinder assembly 47, the piston of which carries a bridle 48, one-half of which is shown at the right-hand side of FIG. 1, and which extends downwardly and terminates in hooked ends 50, which hook under a shoulder 51 formed on the outboard bearing chock 52 carrying the respective outboard bearing 28 of the backup roll 22. By applying pressure to the assemblies 47, the bridles 48 are urged upwardly to cause the roll 22 to bow and the chocks 21 to turn about the engagement points between the convex bearing plates 30 and the housing top 18.

Similarly, the lower backup roll 22 can be bowed by piston and cylinder assemblies 53 carried on beam parts 54 of the baseplate l2 and acting on the extended roll necks of roll 22 through the levers 55 in a manner exactly analogous to that of the roll bending mechanism for the top backup roll 22. For convenience, the backup roll bending mechanism is not shown on the right-hand half of FIG. 2.

The members of each pair of posts 13 and 14 are strapped together at their upper extremities by two housing post straps 56. In the form shown in the drawings, the ends of each strap 56 are bolted to the sides of the housing posts, the strap extending from one end upwardly and sideways and then across between the pair of housing posts. The provision of the straps 56 gives rigidity to the housing posts and permits a less massive construction for the post to be used than would be the case if the posts were unstrapped. While the drawings show the posts bolted to the baseplate 12, each side of the housing could alternatively be formed as an integral closed loop, the posts 13, or 14, a base and the strap 56 being formed as an integral casting. In that case, the two bases of the two housing sides are tied together and the outwardly extending beam parts 54 may be formed integrally with the bases or attached thereto. Also the long bolts 15 are dispensed with and instead short bolts are anchored into the top of the posts 13, 14 and extend upwardly to form the section 33 and screw portion 34, thus forming the connection between the posts and the top 18.

In the construction illustrated, the nuts 31 are tightened before operation to put the bolts 15 into pretension and the column posts into precompression. Before rolling commences, the nuts 35 are driven by the motors 41 to bring the roll gap, between rolls 24, 26 to approximately the correct value for the intended rolling operation, taking into account the enlargement of the roll gap due'to the rolling load and the force applied by the assemblies 43. Next, liquid under pressure is supplied to the cylinders of the assemblies 43 to stress those parts of the bolts 15 between the collared portion 32' and the nut 35; the pressure is selected so that the force applied between the top 18 and housing posts l3, 14 is a proportion, say percent, of the maximum rolling load.

Rolling is then commenced. If the plate is not rolled to the required gauge, the stand can be adjusted, either by operation of the screwdown motors 41, or preferably by adjustment of the pressure to the cylinders of the assemblies 43. For this purpose, an automatic gauge control system such as that known as the Gaugemeter may be provided automatically to control the pressure to the assemblies 43 whenever a gauge error is detected,

The pressure to the cylinders of the backup roll bending assemblies 47; 53 is similarly controlled to adjust the bending of the rolls 22 and thus the shape of the plate being rolled.

In accordance with the provisions of the patent statutes, we

have explained the principle and operation of our invention and have illustrated and described what we consider to represent the best embodiment thereof.

1 claim:

l. A rolling mill stand comprising two pairs of housing posts, the posts constituting each pair defining a space therebetween for receiving one above the other the chocks for at least two rolls, a single housing top member overlying all the housing posts and defining an opening above each housing post, said top having portions for engaging the chocks of the uppermost roll, each post having a bolt anchored thereto and extending upwardly from the upper end of the post, said bolts projecting with a sliding fit through said openings and each bolt terminating in a threaded portion meshing with a nut abutting said top member, power means for rotating said nuts to thereby raise and lower the top member relative to the housing posts, and permit the uppermost roll to be adjusted relative to the lower roll, said top member having a pair of parts extending sideways beyond the planes through the pairs of housing posts and means carried by the extended parts for bending the roll supported by the uppermost chock in each of said spaces.

2. A rolling mill stand as claimed in claim 1 comprising a bending means carried by 'the extended parts include hydraulic piston and cylinder devices.

4. A rolling mill stand as claimed in claim 3 in which each outwardly extending part has the hydraulic piston and cylinder device acting therebetween and the bite of a U-shaped bridle, and with the ends of the bridle engageable with an outboard bearing arrangement on the roll.

5. A rolling mill stand as claimed in claim 1 in which the members of each pair of housing posts are connected together adjacent the upper ends thereof by a rigid strap.

6. A rolling mill stand as claimed in claim 1 in which each housing post is secured to the base of the stand by said bolts extending through the postsf'and which are extensions of the bolts anchored to the posts "and means are provided for pretensioning at least part of the axial length of each bolt.

7. A rolling mill stand as claimed in claim 6 in which each bolt has an outwardly extending portion which is received in a recess in the top of the housing post and a said nut in threaded arrangement with the bolts bears against the underside of the base whereby the part of the bolt between the outwardly extending portion thereof and the nut can be pretensioned by rotating the nut.

8. A rolling mill stand as claimed in claim 7 wherein each housing post has a separate hydraulic piston and cylinder device associated therewith and said devices, when actuated, exert a force between the posts and the housing top to stress the bolts between the outwardly extending portions thereof and their upper end-to permit limited vertical displacement between the housing top and the posts. 

1. A rolling mill stand comprising two pairs of housing posts, the posts constituting each pair defining a space therebetween for receiving one above the other the chocks for at least two rolls, a single housing top member overlying all the housing posts and defining an opening above each housing post, said top having portions for engaging the chocks of the uppermost roll, each post having a bolt anchored thereto and extending upwardly from the upper end of the post, said bolts projecting with a sliding fit through said openings and each bolt terminating in a threaded portion meshing with a nut abutting said top member, power means for rotating said nuts to thereby raise and lower the top member relative to the housing posts, and permit the uppermost roll to be adjusted relative to the lower roll, said top member having a pair of parts extending sideways beyond the planes through the pairs of housing posts and means carried by the extended parts for bending the roll supported by the uppermost chock in each of said spaces.
 2. A rolling mill stand as claimed in claim 1 comprising a baSe for the housing posts, said base having a pair of parts extending sideways beyond the planes through the pairs of housing posts and means carried by said pair of extended parts for bending the roll supported by the lowermost chock in each of said spaces.
 3. A rolling mill stand as claimed in claim 1 in which the roll bending means carried by the extended parts include hydraulic piston and cylinder devices.
 4. A rolling mill stand as claimed in claim 3 in which each outwardly extending part has the hydraulic piston and cylinder device acting therebetween and the bite of a U-shaped bridle, and with the ends of the bridle engageable with an outboard bearing arrangement on the roll.
 5. A rolling mill stand as claimed in claim 1 in which the members of each pair of housing posts are connected together adjacent the upper ends thereof by a rigid strap.
 6. A rolling mill stand as claimed in claim 1 in which each housing post is secured to the base of the stand by said bolts extending through the posts and which are extensions of the bolts anchored to the posts and means are provided for pretensioning at least part of the axial length of each bolt.
 7. A rolling mill stand as claimed in claim 6 in which each bolt has an outwardly extending portion which is received in a recess in the top of the housing post and a said nut in threaded arrangement with the bolts bears against the underside of the base whereby the part of the bolt between the outwardly extending portion thereof and the nut can be pretensioned by rotating the nut.
 8. A rolling mill stand as claimed in claim 7 wherein each housing post has a separate hydraulic piston and cylinder device associated therewith and said devices, when actuated, exert a force between the posts and the housing top to stress the bolts between the outwardly extending portions thereof and their upper end to permit limited vertical displacement between the housing top and the posts. 